A strong heart needs strong arteries. And Scorpius has both. The constellation’s “heart” is the star Antares, a bright orange supergiant. And it’s flanked by bright arteries. One is to the upper right of Antares at nightfall, with the other to the lower left.

Over the centuries, both stars have been known as Al Niyat — an Arabic name that means “the arteries.” To help tell them apart, the one to the upper right is also known as Sigma Scorpii, while the other is Tau Scorpii.

Sigma is a system of at least four stars. At least two of them are similar to Antares. They’re much bigger and heavier than the Sun, and many thousands of times brighter.

The two stars are so close together that not even the biggest telescopes can see them as individual stars — their light blurs into a single point. The system’s other two stars are visible. And those stars are impressive as well — though perhaps not as impressive as the tight binary.

Tau Scorpii consists of a single star. But it, too, is a monster — about 15 times the mass of the Sun, and about 20,000 times brighter.

Antares and its arteries all belong to a big family that includes lots of big, heavy stars. Antares and the Al Niyats are all quite young — no more than about 10 million to 15 million years old. And all of them share an impressive fate: Within a few million years, they’ll explode as supernovae — strong endings for the scorpion’s heart and arteries.

Script by Damond Benningfield

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